Sony Semiconductor Solutions has introduced two new image sensors, IMX420 and IMX428, featuring its 3rd generation CMOS Global Shutter. Both models come with 7 Megapixel resolution, with the IMX420 reaching frames rates of up to 170 fps at 10bit pixel depth. Both sensors achieve an excellent saturation at 25.000e- for a pixel size of 4.5µm. They come equipped with the SLVS-EC interface and new features like High/Low Conversation Gain (HCG), Dual Trigger, Dual ADC and self-triggering, to increase the maximum throughput for object recognition and quality assurance of moving objects in Machine Vision, Robotics, and Factory Automation.
The IMX420 has a scalable bit depth of 8, 10, and 12 bits, and can be programmed for multiple regions of interest (ROI). The IMX428 sensor, optimized for ITS applications, is available only with 12bit, only one ROI window and achieves 35 fps. The innovations of the 3rd generation CMOS Global Shutter Mode sensors deliver clear improvements, mainly in terms of image quality and speed. An increase in performance, based on these improvements, is realized through the improved detection quality in applications with moving objects. The higher saturation, combined with the low readout noise of about 2.5e-, can achieve a maximum dynamic range of 80 dB, resulting in improved light-dark detection that is feasible even in difficult lighting conditions.
Based on different quality improvements, the existing standard interfaces would reach its limits transferring the high data volumes at faster speed. SONY has developed the SLVS-EC standard with 8 lanes which answers the increasing demands in resolution and speed and doubles the maximum output to 18.4 Gbps compared to the second generation (9.5 Gbps).
The IMX420 sensor is equipped with four additional features:
- The High Conversion Gain (HCG) allows the acquisition of images with better quality under low light conditions. This is achieved by increasing the conversion gain of the pixels while keeping the noise contribution of the analog circuit constant. Conversely, the Low Conversion Gain mode (LCG) is used under bright illumination conditions, being realized by lowering the conversion gain of the pixel.
- Dual triggering allows the possibility of different exposure times and gains in different regions of interest, to obtain an individual and effective image acquisition pipeline by using of two external trigger signals.
- Dual ADC can read each pixel with separate gains. By combining the two images off-the-sensor a high dynamic range image can be obtained.
- Self-trigger feature detects a change in the predefined sensing area and acquires an image automatically when this change passes a certain threshold.
The IMX420 and IMX428, as the first sensor models featuring SONY’s 3rd generation CMOS Global Shutter mode, clearly show how the combination of high resolution and high frame rates, along with Global Shutter read-out technology boosts imaging quality and speed into new spheres. With the mass production scheduled around spring 2018, evaluation samples are now available at FRAMOS.